to be

a) He wanted to be honest. And one forced him to promise it. If I want to combine these two information in an one sentence like the following one, will it be correct?

1) He was promised to be honest in life.

b) He was worthy for the post. And he proved it. If I combine these two information and write-

2) He proved himself to be complement/worthy for the post.

will it be correct?

c) We will be careful about our enemies. And for this we will have to collect information. Can I write:

3) We will have to collect information to be careful about our enemies.

At the same way can I write

4) He takes time to be normal in conduct.

5) We will be serious to be successful in the examination.

If you think there are alternative way to rewrite these sentences, please mention these.

Thanks to every member of this forum.